JJ and overcard in big pot

[Aaron_]

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Why is raising the flop right/wrong?

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It's wrong because when an overcard to yours comes on the board and someone bets into the preflop raiser and there are no apparent flush or straight draws, they usually have paired the top card or better and you should usually throw your hand away.

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I guess that's what I wanted to get into on this post. How much of the time does villain have you beat in this situation (given fishy, somewhat aggressive), and is raising to find out worth it?

Any thoughts?